Bioaccumulation and biosorption of stable strontium and 90Sr by Oscillatoria homogenea cyanobacterium

The ability of living filamentous cells of the cyanobacterium Oscillatoria homogenea to separate stable strontium and 90Sr from aqueous solution is demonstrated in this study. On a basis of filamentous cell biovolume, the removal were 43.78 nM x ml x (mm3)-1 and 3129.48 mBq x ml x (mm3)-1 after 240 hour incubation. The optimum pH for strontium uptake is 9±0.3. The increasing biovolume of the blue-green alga elevates sorption. In the liquid culture containing 21.2 mm3 x ml-1 filamentous cells and 1000 nM x ml-1 initial strontium concentration, the maximum strontium removal was 455.34 nM x ml x (mm3)-1. At 1200 Lux illumination, the maximum removal value was 58.62 nM x ml x (mm3)-1, and at the initial strontium concentration of 6590 nM x ml-1, 235.40 nM x ml x (mm3)-1 removal was observed. The experimental data fitted to Langmuir isotherm and the model parameters and correlation coefficient (R2) were qmax = 7.143 μg x (mm3)-1, b 0.003 and 0.99, respectively. (author)